The invention relates to a pump arrangement, in particular a magnetic clutch pump arrangement, having an interior space formed by a pump casing of the pump arrangement, having a containment can which hermetically seals off a chamber surrounded by said containment can with respect to the interior space formed by the pump casing, having an impeller shaft which can be driven in rotation about an axis of rotation, having an impeller which is arranged on one end of the impeller shaft, having an inner rotor arranged on the other end of the impeller shaft, and having an outer rotor which interacts with the inner rotor.
A pump arrangement of said type is known from German patent publication no. DE 10 2004 003 400 A1. In order to increase the range of use, this pump arrangement has a drive rotor formed as an identical part for outer drive elements. This however permits an increase in the range of use only to a particular degree. Above a certain structural size, an adaptation of the rotor size is unavoidable.
European patent publication no. EP 0 814 268 A1 has disclosed a modular construction kit for producing pumps, which modular construction kit is intended to afford the possibility of producing pumps in any desired manner from a small number of structural elements in accordance with the usage requirements. The proposed solution however permits only an exchange of components associated with a single structural size.
The documents cited above however do not take into consideration that, owing to different rotational speeds, delivery heights, delivery volumes and densities of the medium to be delivered, a large range of torques is required for a given hydraulic size.
It is an object of the invention to provide a magnetic clutch pump arrangement in which as large as possible a number of magnetic clutches with different diameters is available for one hydraulic size, and the greatest possible number of different hydraulic sizes can be used for one magnetic clutch size. It is likewise the intention for different containment cans, that is to say different pressure stages and/or materials, to be able to be used within one magnetic clutch size.
This object of the invention is achieved by an adapter element which connects the containment can to the pump casing or to a component assigned to the pump casing, in particular to a casing cover, the adapter element having a mounting flange which, at the side close to the interior space, bears against an abutment surface of the pump casing, in particular of the casing cover.
Through the use of different adapter elements, a modular construction kit is made available which permits efficient structural size configuration for one hydraulic size with different magnetic clutch sizes, or for one magnetic clutch size and different hydraulic sizes.
It is thus possible in a simple manner, by adaptation of the adapter element in terms of shape and/or size, to adapt a magnetic clutch size to different hydraulic sizes. The large range of torques required for the same hydraulic size owing to different rotational speeds, delivery heights, delivery volumes and densities of the medium to be delivered is covered in this way. It is no longer necessary to use the maximum clutch size for all combinations; rather, it is possible in each case for the suitable magnetic clutch size to be adapted to a hydraulic size, with corresponding advantages with regard to energy efficiency, eddy current losses and/or procurement costs. A further advantage of the invention is the reduced number of components that have to be stocked for a pump type series.
In a further refinement, the abutment surface has a region which is recessed in an axial direction and into which a centering ring formed on the mounting flange engages. It is firstly possible for a seal ring to be arranged in the recessed region, and secondly, the adapter element can be aligned exactly and fastened in fluid-tight fashion to the casing cover.
By virtue of the fact that, on the side situated opposite the mounting flange, the adapter element has multiple threaded holes for the fastening of the containment can, it is possible, within one magnetic clutch size, to use or interchange different containment cans of different pressure stages or strengths and/or different materials.
According to the invention, on the side situated opposite the mounting flange, a ring is provided which extends further in the axial direction into the interior space, which ring forms a run-on safeguard and prevents contact between the outer rotor and the containment can.
To improve the flow guidance of the medium, and for easier and thus cheaper production by casting, the outer contour of the adapter element has a substantially conical profile.
Here, the adapter element preferably narrows, substantially proceeding from the mounting flange toward the ring.
In a further refinement, it is provided that that end of the outer rotor which points in the direction of the casing cover has a radially encircling projection. In this way, the radial spacing of the outer rotor to the ring for normal operation can be produced in an exact manner.
For the same reason, alternatively or in addition, the projection may be formed on the inner side of the ring.
In a further exemplary embodiment of the invention, it is provided that the end of the outer rotor which points in the direction of the casing cover has a region of reduced outer diameter. The mounting capability of the adapter element in the case of small clutch diameters is thus ensured.
In a further advantageous refinement, between the impeller and inner rotor, there is arranged a bearing arrangement which is operatively connected to the impeller shaft, which can be driven rotatably about the axis of rotation.
In the context of the invention, it is proposed that, in a further embodiment, a spring device is arranged between the inner rotor and the bearing arrangement.
According to the invention, in one embodiment, between the spring device and the inner rotor, there is situated a spacer sleeve, which is pushed onto the impeller shaft and by means of which the inner rotor extends deeper into the outer rotor in an axial direction. Thus, the magnets of the inner rotor and the magnets of the outer rotor are optimally aligned with respect to one another in order to ensure an optimum transmission of power from the outer rotor to the inner rotor.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.